In-process diameter measurement gage

ABSTRACT

An In-Process Diameter Gage comprises a Position Detection Subsystem, preferably an optical switch and trigger, a Dimension Measurement Subsystem, preferably comprising a wheel of known diameter and a rotation encoder, and a Data Processing Subsystem, all configured and arranged to determine a dimensional property of a rotating part, such as diameter.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims benefit of and priority to U.S. ProvisionalApplication Ser. No. 62/344,369, filed on Jun. 1, 2016, the entirecontents of which are incorporated herein for all purposes.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION Field of the Invention

The inventions disclosed and taught herein relate generally tometrological devices and processes; and more specifically related to anin-process diameter measurement gage and methods.

Description of the Related Art

U.S. Pat. No. 4,700,484, owned by Applicant, states “An apparatus formeasuring the diameter of an object is disclosed. A rotatable wheel ofknown diameter capable of movement in three axes is contacted with anobject capable of rotation. The wheel is attached to a shaft encoder,which produces pulses as the wheel rotates. As the object is rotated,start and end reference marks are sensed and the pulses produced by theshaft encoder are counted. A microprocessor calculates the diameter ofthe object knowing the wheel diameter and counts per revolution and thecounts per revolution of the object. The apparatus can be adapted tomeasure the internal or external diameter of smooth objects or theinternal or external pitch diameter of threaded objects. The apparatuscan also use a calibrated object to measure the diameter of a wheel ofunknown diameter to allow the wheel to be used in later measurements.”

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The following figures form part of the present specification and areincluded to further demonstrate certain aspects of the presentinvention. The invention may be better understood by reference to one ormore of these figures in combination with the detailed description ofspecific embodiments presented herein.

FIG. 1 illustrates a conceptual overview of one of many possibleembodiments of an In-Process Diameter Measurement Gage.

FIG. 2 illustrates an embodiment of a Dimension Measurement Subsystemsuitable for use with the present invention.

FIG. 3 illustrates one of many “Settings” screens from an embodiment ofa Data Processing Subsystem suitable for use with the present invention.

FIG. 4 illustrates an embodiment of the present invention during ameasurement cycle.

FIG. 5 illustrates the desired alignment between the contact wheel andthe part.

While the inventions disclosed herein are susceptible to variousmodifications and alternative forms, only a few specific embodimentshave been shown by way of example in the drawings and are described indetail below. The figures and detailed descriptions of these specificembodiments are not intended to limit the breadth or scope of theinventive concepts or the appended claims in any manner. Rather, thefigures and detailed written descriptions are provided to illustrate theinventive concepts to a person of ordinary skill in the art and toenable such person to make and use the inventive concepts.

DETAILED DESCRIPTION

The Figures described above and the written description of specificstructures and functions below are presented not to limit the scope ofwhat Applicants have invented or the scope of the appended claims.Rather, the Figures and written description are provided to teach anyperson skilled in the art how to make and use the inventions for whichpatent protection is sought. Those skilled in the art will appreciatethat not all features of a commercial embodiment of the inventions aredescribed or shown for the sake of clarity and understanding. Persons ofskill in this art will also appreciate that the development of an actualcommercial embodiment incorporating some or all aspects of the presentinventions will require numerous implementation-specific decisions toachieve the developer's ultimate goal for the commercial embodiment.Such implementation-specific decisions may include, and likely are notlimited to, compliance with system-related, business-related,government-related and other constraints, which may vary by specificimplementation, location and from time to time. While a developer'sefforts might be complex and time-consuming in an absolute sense, suchefforts would be, nevertheless, a routine undertaking for those of skillin this art having benefit of this disclosure. It must be understoodthat the inventions disclosed and taught herein are susceptible tonumerous and various modifications and alternative forms. The use of asingular term, such as, but not limited to, “a,” is not intended aslimiting of the number of items. Also, the use of relational terms, suchas, but not limited to, “top,” “bottom,” “left,” “right,” “upper,”“lower,” “down,” “up,” “side,” and the like are used in the writtendescription for clarity in specific reference to the Figures and are notintended to limit the scope of the invention or the appended claims.

Particular embodiments of the invention may be described below withreference to block diagrams and/or operational illustrations of methods.It will be understood that each block of the block diagrams and/oroperational illustrations, and combinations of blocks in the blockdiagrams and/or operational illustrations, can be implemented by analogand/or digital hardware, and/or computer program instructions. Suchcomputer program instructions may be provided to a processor of ageneral-purpose computer, special purpose computer, ASIC, and/or otherprogrammable data processing system. The executed instructions maycreate structures and functions for implementing the actions specifiedin the block diagrams and/or operational illustrations. In somealternate implementations, the functions/actions/structures noted in thefigures may occur out of the order noted in the block diagrams and/oroperational illustrations. For example, two operations shown asoccurring in succession, in fact, may be executed substantiallyconcurrently or the operations may be executed in the reverse order,depending upon the functionality/acts/structure involved.

We have invented a system configured to determine or measure one or moredimensional properties of a manufactured item or part, preferably, butnot exclusively during the manufacturing phase. For example and withoutlimitation, the system can be used to determine or measure, among otherparameters, inside or outside diameter, thread profile parameters, suchas minor diameter, pitch diameter, major diameter, pitch, flank angle,and thread length. For purposes of this disclosure, the item beingmeasured will be referred to as the “part.” In a preferredimplementation of this invention, one or more dimensional properties ofthe part, such as a threaded pipe, is measured while the part isrotating, such as during manufacture. For example, measurements may betaken while the part is rotating at speeds typically associated withmachining or grinding operations. More specifically, measurement may betaken at rotational speeds up to about 400 SFM and higher. Accuraciesand repeatability down to at least about 0.0002″ (0.2 mils) areachievable and the diameter that the system can determine is effectivelyunlimited. The system eliminates the need for inaccurate pi (π) tapes orcustom-built micrometers, which can require two or even three people tomake accurate measurements. For example, when the invention isimplemented with a CNC manufacturing device, the invention may be calledfor by the CNC program from the tool holder and implemented to makemeasurements at the proper time and location. Alternately, the inventionmay be implemented automatically and continuously during manufacture ormay be implement manually as desired. Further, the dimensionalinformation generated by the invention may be integrated into the CNCprogram. For purposes of this disclosure, a lathe will be used as themanufacturing device and the manufactured part will be a threaded pipe.It will be understood that the invention is not limited to this specificmanufacturing device or this specific manufactured part.

Our system comprises three main subsystems: a Position DetectionSubsystem, a Dimension Measurement Subsystem and a Data Processingsubsystem. The Position Detection Subsystem is configured to detect andindicate a specific rotational position of the part during themeasurement process. By specific rotational position, it is meant atleast a time-referenced location or event, and not necessarily acoordinate location in space, although the latter is within the scope ofthe present invention. A Position Detection Subsystem preferablycomprises an optical switch or detector in which, for example, atrigger, such as a reflector, is attached to a rotating component of thelathe whose rotation is representative, directly or indirectly, of therotation (e.g., revolutions per minute) of the part. In oneimplementation, the optical detector is a light switch and reflectorcombination, the output of which is, for example, a voltage pulse everytime the reflector passes through the light beam. The OPB740 opticaldetector available from Optek Technology has been found suitable forthis purpose, and the specifications and operational characteristics ofthat device are incorporated herein by reference.

It should be appreciated that the Position Detection Subsystem does nothave to detect the absolute (angular) positon of the pipe relative tothe lathe or other, or other reference point, but rather only arepeatable, relative position, such as the rotating reflector passingthrough the fixed light beam. While it is presently preferred that thePosition Detection Subsystem indicate simply a completed revolution ofthe part, it may be desirable in some embodiments of the invention forthe Position Detection Subsystem to detect the absolute position of thepart in space. For example, triggers (e.g., reflectors) could be located90° apart, and a datum of the part to be measure can be oriented in thelathe relative to one or more of these triggers.

Preferably, the Position Detection Subsystem is mounted in an out-of-theway, or remote, or protected, or sealed location on the lathe so thatthe subsystem is not damaged or fouled during machining operations.Because of the dedicated mounting location, it is desired, but notrequired, that the Position Detection Subsystem be hard wired for power.Alternately, the Position Detection Subsystem can be battery powered. Itis preferred, but not required, that the Position Detection Subsystemreport a condition of the power source through the communicationcomponent.

The Position Detection Subsystem also may comprise a wired and/orwireless communication component, such as a radio frequency transmitter,configured to transmit a signal representative of the pipe position,including, but not limited to, an analog signal, such as a voltage pulseor digital data, or both. It will be appreciated that this communicationcomponent may be a one-way communication pathway from the PositionDetection Subsystem to the Dimension Measurement Subsystem and/or to theData Processing Subsystem. In other words, in certain embodiments, itmay not be necessary for the Dimension Measurement Subsystem or the DataProcessing Subsystem to send data or information to the PositionDetection Subsystem.

In a preferred embodiment, the Position Detection Subsystem may comprisea one-way wireless communication pathway with the Dimension MeasurementSubsystem. In this embodiment, the communication pathway is desired tobe as instantaneous as possible and with repeatable or consistentlatency. Inconsistency or variability in latency or a varying delay ofthis signal transmission will adversely affect the accuracy of thedimensional measurements because the relationship between the completionof a part revolution and part measurements will vary along with thevarying latency. One form of acceptable wireless communication protocolwith repeatable, consistent latency is a simple analog radio signal. Forexample, the Texas Instrument chip model no. CC1101 is suitable for thisone-way analog communication link, and the specifications andoperational characteristics are incorporated herein by reference.

Alternately, a wireless digital communication protocol may be used ifthe latency, and variability of the latency does not adversely affectthe accuracy and/or precision of the ultimate measurement. For example,if the embodiment under consideration merely requires an indication thata part revolution has been completed, a wireless digital communicationprotocol in which the same predetermined digital “word” is sent everytime to indicate that a part revolution has been completed, the latencyand variability of the latency, if any, in such communications likelywill be acceptable for purposes of this invention. Still further, thereare known methodologies for dealing with varying communicationlatencies, such as transmitting time stamps with the data, and/or otherinformation that allows a processor, such as the Dimension MeasurementSubsystem or the Data Processing Subsystem, to correct for the varyinglatency. All of these communication protocols and others known, but notdiscussed herein, may be used with various embodiments of the inventionsdisclosed herein.

The Dimension Measurement Subsystem, sometimes referred to as a gagehead, may comprise a one or more transducers configured to measure ordetermine a physical attribute, property or parameter of the part. TheDimension Measurement Subsystem may be mounted to or adjacent the lathe,so that it can be manually or automatically moved into measurementpositon, as desired. As mentioned above, the Dimension MeasurementSubsystem also can be implemented as a machine tool retrievable by thetool arm, as desired. It is preferred, but not required, that theDimension Measurement Subsystem be battery powered and comprise a firstcommunication component configured to receive a wired or wirelesscommunication from the Position Detection Subsystems. For example, thefirst communication component may comprise a radio frequency receiverconfigured to receive the radio frequency signal transmitted by thePosition Detection Subsystem.

To measure or determine, for example, the diameter of the part (e.g.,pipe) or of an area on the part, the Dimension Measurement Subsystem maybe configured as a perimeter transducer comprising a contact wheel ofknown diameter coupled to a rotation encoder. For example and notlimitation, a rotation encoder manufactured by BEI Sensor, model H25,having a resolution of about 12,500 increments per revolution, and evenup to about 50,000 increments per revolution, has been found suitablefor determining diameters with this invention, and the specificationsand operational characteristics of that device are incorporated hereinby reference.

While absolute rotation encoders may be utilized, incremental rotationencoders are sufficient for purposes of this invention. The contactwheel makes contact with the part at the location to be measured and thewheel is biased against the pipe with a predetermined force sufficientto maintain measurement contact between the wheel and the pipe,preferably without causing appreciable elastic or plastic deformation.The contact wheel may be made from the same material as the part, butpreferably, the wheel is made from hardened steel. For example, analuminum contact wheel may be used for an aluminum pipe. However, apreferred embodiment contemplates a hardened steel contact wheel (e.g.,HRC of about 65) for all parts. In such circumstances, any differencesin material properties between the wheel and part (such as, modulus ofelasticity) may be accounted for as described herein. The contact wheelshould be aligned with the part to minimize skipping, skidding, sliding,or other measurement contact errors. Further, it is preferred, but notrequired that the contact portion of the contact wheel have a transverseradius equal to the radius of the wheel. Such structural arrangementminimizes the measurement error that can be caused by misaligned (e.g.,out of normal) contact wheel to the pipe. Alternately, the contactportion of the wheel can be dimensioned to measure individual threaddiameters or thread artifacts as desired.

In addition, the Dimension Measurement Subsystem preferably compriseslogic/processing circuits and/or components configured to process data,such as by accumulating, encoder pulses representative of the rotationof the contact wheel. For example, and not limitation, such circuitryand components may comprise one or more counters, buffers, memorylocations and/or software. In a preferred embodiment, when the PositionDetection Subsystem transmits a signal indicating the relative positionof the rotating component and therefore, of the part to be measured(e.g., pipe), the Dimension Measurement Subsystem reads and resets theaccumulated encoder counts and writes the accumulated count to a buffer,memory location, or communication component. The Dimension MeasurementSubsystem circuits and components preferably continuously accumulate thenumber of encoder pulses, such as by incrementing, until the next signalfrom the Position Detection Subsystem is received at which time thenumber of accumulated encoder pulses are again written to a buffer,memory location, or communication component and the counter reset tozero counts.

In general, it is preferred, but not required that the counter, bufferor memory location that increments the encoder pulse count have acapacity greater than at least the number of pulses that can begenerated during one revolution of the contact wheel. For example, ifthe rotational encoder can generated 50,000 pulses per revolution, it isdesired that the counter, buffer or memory location that stores thepulse count have a capacity greater than 50,000 counts or can store datarepresenting a count greater than 50,000. It is also preferred that thecounter, buffer or memory location that increments encoder pulse countshave a capacity greater than the number of pulses for a revolution ofthe part, and most preferably greater than about 4 to about 10revolutions of the part. The Dimension Measurement System also maycomprise a removable memory, such as a memory card, on which pulsecounts, revolution signals and other data may be written as a backup tothe data transmission.

In general, it also is preferred that the contact wheel diameter (orradius) be smaller than the diameter (or radius) of the part to bemeasured. For example, in a preferred embodiment, the contact wheel is aprecision component made from hardened steel and having a diameter of3.75 inches. It is preferred that the part diameter always be greaterthan the contact wheel diameter. It will be appreciated that when thecontact wheel diameter is less than the part diameter, the contact wheelwill complete more than one revolution before the part completes onerevolution. In other words, and for example only, the contact wheel maycomplete 4.2 revolutions between position signals generated by thePosition Detection Subsystem (indicating one revolution of the part).Thus, it may be beneficial to configure the counter, buffer or memorylocation that increments the encoder pulse count to have capacitygreater than a multiple of the encoder pulses generated by onerevolution of the contact wheel. In the example mentioned above, thecounter, buffer or memory location may be configured to have a capacitygreater than 500,000 counts or to store data representing a countgreater than 500,000.

Depending on the specific implementation of the Dimension MeasurementSubsystem, each time a part position signal is received by the DimensionMeasurement Subsystem, the accumulated pulse count (e.g., 210,000counts) may be transmitted to the Data Processing Subsystem.Alternately, the system can be configured to transmit counts only aftera specified number of part revolutions have occurred. For example, if itis desired to determine part diameter from data generated from 5 partrevolutions, the Dimension Measurement Subsystem may be configured totransmit to the Data Processing Subsystem a count representative of 5revolutions of the part (e.g., 1,050,000 counts). In these particularembodiments, the Dimension Measurement Subsystem has limited dataprocessing capabilities, and may or may not be configured to calculateor determine the actual part dimension, such as diameter. Rather theData Processing Subsystem may be configured to receive information fromthe Dimension Measurement Subsystem (and the Position DetectionSubsystem, if desired) and thereafter calculate or determine (anddisplay) the actual part dimension, such as diameter. Alternately,embodiments of system may comprise Dimension Measurement Subsystems thathave more sophisticated data processing and visual display capabilities,such as the capability to calculate or determine the desired partdimension, and/or to display the measured part dimension. Still further,the Dimension Measurement Subsystem can be configured to send an alertsignal if the part is rotating at a speed greater than a specifiedmaximum, or slower than a specified minimum. The Dimension MeasurementSubsystem also can be configured to detect count variations during apart measurement cycle, which indicate a surface speed change orovality.

In general, the data collection process is repeated a preselected numberof times, such as about 4 to about 10 part revolutions, until sufficientdata has been collected to ensure an accurate measurement of the part.The data from the Dimension Measurement Subsystem may be transmitted tothe Data Processing Subsystem by radio frequency, such as Bluetoothcommunication protocol, other wireless or radio frequency data protocol,or by hard wire.

In addition to or in place of a contact wheel rotation encoder, asdescribed above, the Dimension Measurement Subsystem (or gage head) mayalso comprise an inclinometer, a radial displacement transducer, asurface roughness transducer and/or an axial displacement transducer. Itwill be appreciated that the terms “radial” and “axial” are relative tothe part (e.g., pipe). An inclinometer can be used to measure angles,such as flank or thread angle; a radial displacement transducer, such asan LVDT, can be used to determine properties such as ovality and threadheight; an axial displacement transducer can be used to determineproperties such as thread pitch or length; and a surface roughnesstransducer can be configured to measure the surface roughness of themanufactured part. As discussed with respect to diameter, the DimensionMeasurement Subsystem may be configured to accumulate the data (whetherdigital or analog) from these transducers and transmit the data to theData Processing Subsystem, preferably after one or more revolutions ofthe part, as indicated by the Position Detection Subsystem. Alternately,the Dimension Measurement Subsystem may accumulate data from thetransducers, manipulate or transform the data, and then transmit data tothe Data Processing Subsystem.

The Data Processing Subsystem, which may be a dedicated centralprocessing unit (CPU) with display, a smartphone, a tablet or the like,is configured to process information and data from the DimensionMeasurement Subsystem (and Position Detection System, as desired) anddisplay the measured, calculated or determined dimensional parameter,such as diameter, based on received and inputted data. For example, andwithout limitation, if the system is programmed to require 4 partrevolutions per measurement, and the Dimension Measurement Subsystemrecords about 200,000 contact wheel encoder pulses for each partrevolution, the average encoder pulses per part revolution (e.g.,200,000) may be used along with the known diameter of the contact wheelto calculate the diameter of the pipe using known relationships betweencircumference and diameter. Similar calculations or determinations maybe made for other dimensional properties from data from othertransducers. For example, a diameter measurement may be made at one partlocation, then the Dimension Measurement Subsystem relocated a knowndistance (e.g., 1 inch) to another location and diameter measurementstaken at that location. In addition to diameters of the part, the taperof the part between the measurement locations can be determined. Stillfurther, run out of the part can be calculated from data from one ormore revolutions of the part.

The communication link between the Dimension Measurement Subsystem andthe Data Processing Subsystem may be wired or wireless, and may utilizea digital or other communication protocol because consistent latency isnot as important, if at all, as compared to the Position DetectionSubsystem to Dimension Measurement Subsystem link. Moreover, it isdesired that substantive data be transmitted to the Data ProcessingSubsystem, whereas the information transmitted to the DimensionMeasurement Subsystem by the Position Detection Subsystems preferablyneed only be the occurrence of an event, and not necessarily substantivedata.

The Data Processing Subsystem may comprise error correction algorithmsand other algorithms such as direction of rotation algorithms. The DataProcessing Subsystem may also allow the operator to enter informationabout the setup that can affect the measured or calculated dimension orproperty. This information may include the contact wheel diameter, thepart temperature, transducer temperature (e.g., wheel temperature), partmaterial, and taper of the part, for example.

It will be appreciated that a Position Detection Subsystem and aDimension Measurement Subsystem can be deployed on a plurality ofmanufacturing machines in a facility, so long as the wirelesscommunication link between the subsystems on an individual machine donot interfere with the communication links on adjacent machines. Eachmachine (e.g., each Dimension Measurement Subsystem on a machine) maycommunicate, such as by Bluetooth protocol, with a primary DataProcessing Subsystem for the facility and/or with secondary dataprocessing subsystems or display subsystems associated with eachmachine, including smart phones and tablets.

Turning now to the Figures, which illustrate one or more non-limitingembodiments of the disclosed inventions, FIG. 1 illustrates an overviewof an In-Process Diameter Measurement Gage 100 utilizing aspects ofinventions discussed above. Illustrated in FIG. 1 is a machine 102, suchas a lathe, comprising a motor 104, a shaft 106 and a chuck 108. Part110, such as a threaded pipe or other component, is illustrated securedto the chuck, as is typical during machining operations. The system 100is illustrated to comprise a Position Detection Subsystem 120, aDimension Measurement Subsystem 130, and a Data Processing Subsystem140.

As described above, the Position Detection Subsystem comprises anoptical sensor 122 and an optical sensor trigger 124. The trigger 124,such as a reflector, is affixed to a component of the machine 102, suchas shaft 106, that is representative of the rotation of part 110. Thesensor 122 is mounted in operational alignment with the trigger 124 todetect when the trigger passes by the optical sensor 122, as anindication of a complete revolution of the part. The sensor 122 isillustrated to be wired to a control unit 126, which may receive hardwired power or be battery powered. The control unit 126 receivesinformation from the sensor 122, such as a voltage pulse or spike whenthe trigger 124 passes the sensor 122, and manipulates that information,as required, for transmission to the Dimension Measurement Subsystem130.

The control unit 126 comprises a transmitter configured to wirelesslytransmit a single, predetermined digital word to the DimensionMeasurement Subsystem, the receipt of which indicates that the part 110has completed one revolution. In this embodiment, the digital wordtransmitted by the control unit 126 has no meaning other than the sensor122 has detected a triggering event. Although not shown, control unit126, also may communicate with the Data Processing Unit 140, eitherwired or wirelessly, to communicate parameters of operation, such asrotational speed of the part (RPM), or battery life, or power status.

As described above, and referring also to FIG. 2, the DimensionMeasurement Subsystem 130 comprises a contact wheel 202, which ispreferably a hardened steel wheel having a precision ground diameterbetween about 2 inches and about 6 inches, and most preferably about3.75 inches. The wheel 202 is coupled, preferably removably coupled, toan encoding transducer 204 configured to generate a signals indicativeof rotation of the wheel. For example, as described above, the encoder204 may generate about 50,000 signals (e.g., pulses) for each completerevolution of the wheel 202. In other words, for a wheel 202 having adiameter of 3.75 inches, each encoder 204 pulse represents about 0.00024inches of circumferential travel by the wheel 202. The wheel 202 and theencoder 204 are supported by a body 206, which is in turn supported by ashank 208. The shank 208 may be configured to be mounted in a standardtool block, so that it can rotate and contact the part to be measured.The body 206 comprises a radial translation assembly 210 configured toallow the wheel 202 and encoder 204 to displace radially toward and awayfrom the part (shown in FIG. 1). It is preferred that the radialtranslation assembly 210 includes a biasing element, such as a spring,that causes the wheel 202 to displace toward the part 110. The biasingelement may be configured to apply a force between the wheel 202 and thepart 110 to ensure accurate tracking of the wheel 202 on the part 110.It is preferred that the applied force be in a range of about 5 lbf toabout 10 lbf, and most preferably about 8 lbf±1 lbf. In a preferredimplementation, the body includes at least one visual indicator, such asa green LED, that illuminates when the correct tracking force is appliedto the part 110.

As discussed above, the Dimension Measurement Subsystem 130 alsocomprises electronic circuits on one or more circuit boards 220providing an encoder data management component, and at least a wired orwireless receiver component for receiving transmissions from thePosition Detection Subsystem 120, and a wired or wireless communicationcomponent for transmitting information to the Data Processing Subsystem140.

As disclosed above, the Data Processing Subsystem 140, may comprise adedicated processing unit with data input functionality and visualdisplay, a laptop or desktop computer, a computer table or smart phone.In some implementations, the Data Processing Subsystem 140 will comprisea dedicated processing unit that is mounted to or adjacent the machine102. In other implementations, the Data Processing Subsystem 140 willcomprise a computer at a location remote from the machine 102. It ispreferred that the Data Processing System 140 be configured to receivedata from at least the Dimension Measurement Subsystem 130 and tocalculate or determine the dimensional measurement of the part, such asdiameter. The Data Processing Subsystem may also be configured toreceive data from the Position Detection Subsystem for purposes ofdimensional calculation or determination, or for purposes of systemoperational characteristics or both.

FIG. 3 illustrates one of many possible “Settings” screens 300 on a DataProcessing Subsystem 140 suitable for use with the present inventions.The Data Processing Subsystem 140 screen 300 may display a field 302 forinputting the known diameter of the contact wheel 202, such as 3.75inches. Additionally, a measured temperature of the contact wheel and ameasured temperature of the part 102 may be manually entered orautomatically uploaded into fields 304 and 306. The material of thepart, such as cast steel, cold rolled steel, stainless steel, othersteel, malleable iron, aluminum alloys, monel alloys, Inconel alloys,pure titanium, 6Al4V titanium, or others may be inputted into field 308.If desired or required, screen 300 can allow the operator to select adiscrete channel for wireless communication between the Data ProcessingSubsystem 140 and the Dimension Measurement Subsystem 130.

The Data Processing Subsystem 140 also may provide a contact wheel 202calibration or compensation capability as illustrated by field 310. Forexample, a certified master part (not shown) of known diameter (e.g.,8.02211 inches) may be chucked into the machine 102, and the In-ProcessDiameter Gage 100 set up as disclosed herein. Thereafter, the system 100may be used to measure the diameter of the certified master part. If themeasured diameter of the certified master part is different than theknown diameter of the certified master part (i.e., 8.02211 inches), themeasured diameter can be used along with the known diameter to calculatean effective or calibrated or compensated diameter of the contact wheel202 using an equation similar to the following:

WheelDiameter_(CORRECTED)=MasterDiameter_(SPECIFIED)×[WheelDiameter_(SPECIFIED)/Measured Result].

As shown in FIG. 3, the calibration routine on the Data ProcessingSubsystem has calculated the effective diameter of the supposed 3.75inches diameter wheel to be 3.618 inches, as shown in field 302.

The Data Processing Subsystem 140 also may provide a measurement errorcorrection based on the temperatures of the part 110 and wheel 202 andthe differences between the modulus of elasticities of the contact wheel202 and the part 110. For example, if the contact wheel 202 is hardenedsteel and is biased against the part 110 with a force of between about 5lbf and about 10 lbf, there may be elastic deformation of the part 110at the contact point of the wheel 202 sufficient to affect the accuracyof the measurements. The Data Processing Subsystem 140 can be configuredto compute an error correction or measurement compensation based on thedifferences in material properties, temperature, and biasing force.

FIG. 4 illustrates the preferred alignment between the part 102 and theDimension Measurement Subsystem 130 to ensure accurate dimensionalmeasurements. When the part 110 is coupled to the rotating machinery,such as chucked to a lathe, the chuck 104 and the part 110 will definean axial axis “X” and two orthogonal axes “Y” and “Z”. It is preferredthat the plane or face of the contact wheel 202 be parallel to the Y andZ axes within about 0.005 inch across the face of the contact wheel 202.

FIG. 5 illustrates the In-Process Diameter Gage 100 in use measuring thediameter of a part 102. The Position Detection Subsystem 120 comprisingoptical switch 122 and trigger 124 are shown relative to the chuck 108,and in position to cause a signal indicative of full revolution of thepart 102. The Dimension Measurement Subsystem 130 comprising contactwheel 202 is shown in biased contact with the outer surface of part 110.As the part 110 rotates in a clockwise direction, the wheel 202 rotatesin a counterclockwise direction, as illustrated. Because of the relativesizes of the wheel 202 and the part 110, the wheel 202 will completemultiple revolutions for each complete revolution of the part 110. Asillustrated in FIG. 5, the wheel 202 will complete four revolutions andpart of a fifth revolution before the optical switch is triggeredindicating a complete revolution of the part 110. Assuming the DimensionMeasurement Subsystem 130 encodes 50,000 counts per wheel 202revolution, the Dimension Measurement Subsystem 130 will accumulateabout 235,714 counts per part 110 revolution. During a measurementcycle, the first time the trigger 124 passes the optical switch 122, theDimension Measurement System starts measuring the part by accumulatingrotary encoder 204 counts. Each time the trigger passes the opticalswitch, a counter is incremented by 1 revolution until the presentnumber of part revolutions has been achieved. Thereafter, the DataProcessing Subsystem can display the determined measurement. Asdiscussed above, this count data can be transmitted to the DataProcessing Subsystem upon completion of each part revolution (e.g.,after the optical switch 122 signal has been received) or after thecompletion of the set number of part revolutions have been completed(such as 5 part revolutions).

Other and further embodiments utilizing one or more aspects of theinventions described above can be devised without departing from thespirit of our invention. For example, the rotary encoder 204 may bereplaced with other encoders or transducers, as discussed above, orother encoders or transducer may be included with the rotary encoder204. As further example, a combined rotary encoder and axialdisplacement transducer may be used to measure thread diameter andthread lead or pitch. Further, the various methods and embodiments ofthe methods of manufacture and assembly of the system, as well aslocation specifications, can be included in combination with each otherto produce variations of the disclosed methods and embodiments.Discussion of singular elements can include plural elements andvice-versa.

The order of steps can occur in a variety of sequences unless otherwisespecifically limited. The various steps described herein can be combinedwith other steps, interlineated with the stated steps, and/or split intomultiple steps. Similarly, elements have been described functionally andcan be embodied as separate components or can be combined intocomponents having multiple functions.

The inventions have been described in the context of preferred and otherembodiments and not every embodiment of the invention has beendescribed. Obvious modifications and alterations to the describedembodiments are available to those of ordinary skill in the art. Thedisclosed and undisclosed embodiments are not intended to limit orrestrict the scope or applicability of the invention conceived of by theApplicants, but rather, in conformity with the patent laws, Applicantsintend to fully protect all such modifications and improvements thatcome within the scope or range of equivalent of the following claims.

What is claimed is:
 1. A measurement system, comprising, a positiondetection subsystem configured to detect when a rotating part hascomplete a revolution, a transmitter associated with the positiondetection subsystem and configured to transmit a signal representativeof a completed revolution; a dimension measurement subsystem comprisinga dimensional transducer configured to contact the rotating part andgenerate data representative of a dimensional property; a communicationcomponent associated with the dimension measurement subsystem andconfigured to receive a signal from the position detection subsystem,and to transmit data; and a data processing subsystem configured toreceive data from the dimension measurement subsystem and to determineand display a value of the dimensional property of the part from thereceived data.
 2. The measurement system of claim 1, wherein the signalfrom the position detection subsystem has consistent latency.
 3. Themeasurement system of claim 2, wherein the dimensional property of thepart is diameter.
 4. The measurement system of claim 3, wherein thedimensional transducer comprises a contact wheel of known diameter and arotation encoder configured to generate a plurality of signals for eachrevolution of the wheel.
 5. The measurement system of claim 4, whereinthe position detector subsystem comprises an optical switch with a fieldof view, and a trigger that rotates in time with the part into and outof the field of view once every revolution of the part.
 6. Themeasurement system of claim 5, wherein the data generated by thedimensional measurement subsystem comprises a total number of signalsfor at least one revolution of the part.
 7. The measurement system ofclaim 6, wherein the data generated by the dimensional measurementsubsystem comprises a total number of signals for at least 4 to 10revolutions of the part.
 8. The measurement system of claim 3, whereinthe data processing subsystem configured to determine diameter run outof the part.
 9. The measurement system of claim 6, wherein the partrotates at a speed of between about 50 SFM and about 400 SFM.
 10. Themeasurement system of claim 2, wherein the dimensional property istaper.
 11. The measurement system of claim 4, wherein the contact wheelis biased against the part with a force between about 7 lbf and about 9lbf.
 12. A method of measuring a dimension of a rotating part,comprising, providing a rotating part from which a dimensionalmeasurement is required; generating a signal representative of when therotating part completes a revolution; contacting a measurement devicewith a wheel of known diameter with a location on the rotating part tobe measured; biasing the wheel against the rotating part with apredetermined force; generating a signal for each incremental revolutionof the wheel, so that a plurality of signals are generated for eachcomplete revolution of the wheel; transmitting the signal that isrepresentative of a completed revolution of the part to the measurementdevice; generating data representative of the number of plurality ofsignals generated by the wheel for at least one complete revolution ofthe part; determining a dimensional property of the rotating part fromthe data and the diameter of the wheel; and displaying the dimensionalproperty.
 13. The method of claim 12, wherein transmitting the signalrepresentative of part revolution to the measurement device is done withconsistent latency.
 14. The method of claim 13, wherein the dimensionalproperty of the part is diameter.
 15. The method of claim 14, whereinthe measurement device comprises a contact wheel of known diameter and arotation encoder configured to generate a plurality of signals for eachrevolution of the wheel.
 16. The method of claim 15, wherein generatinga signal representative of when the rotating part completes a revolutioncomprises an optical switch with a field of view, and a trigger thatrotates in time with the part into and out of the field of view onceevery revolution of the part.
 17. The method of claim 16, wherein thedata representative of the number of plurality of signals generated bythe wheel comprises a total number of signals for at least 4 to 10revolutions of the part.
 18. The method of claim 14, further comprisingdetermining a diameter run out of the part.
 19. The method of claim 13,wherein the part rotates at a speed of between about 50 SFM and about400 SFM.
 20. The method of claim 13, wherein the biasing force isbetween about 7 lbf and about 9 lbf.